using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplication16
{
    class Graph
    {
        public static List<int> add(List<int> tree, int n)
        {
            Console.WriteLine("Введите число");
            n = Int32.Parse(Console.ReadLine());
            tree.Add(n);
            for (int i = 0; i <= tree.Count; i++)
            {
                Console.WriteLine(tree[i]);
            }
            return tree;
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            List<int> Tree = new List<int>() { -1 };
            Graph T = new Graph();
                        
            
            //Console.WriteLine("Введите число");
            //n = Int32.Parse(Console.ReadLine());

            for (int i = 0; i < Tree.Count; i++)
            {
                Console.Write(Tree[i]+" ");
            }

        }
    }
}